Tick-borne encephalitis vaccine (whole virus, inactivated)

Tick-borne encephalitis (TBE) is a disease caused by the TBE virus (TBEV), transmitted by ticks from the genus Ixodes. The disease course is variable. Some patients will be asymptomatic or experience a mild febrile illness, while others will experience the full course including neurological symptoms. TBE often manifests in a biphasic manner, with patients experiencing a flu-like illness followed by a variable asymptomatic period and then a second phase characterized by various neurological symptoms falling under the categorizations of meningitis, diffuse/focal meningoencephalitis, and meningoencephalomyelitis. While some patients recover fully following neurological TBE, neurological sequelae can last for years and rare chronic forms of the disease have also been noted. Due to a paucity of effective safe and effective acute therapeutic agents, vaccination remains the most important defence against TBE in endemic areas.

TICOVAC (also known as TicoVac or FSME-IMMUN) was the first approved vaccine against TBE in Europe, first approved in 1976. A second very similar vaccine, Encepur, followed in 1991. Both vaccines are based on formaldehyde-inactivated whole virus. Although TICOVAC was originally based on a master seed virus passaged in mouse brain and then propagated in chicken embryo fibroblast (CEF) cells, since the 1990's, the whole process has been carried out in CEF cells only.

Originally developed by Baxter International Inc., TICOVAC was subsequently acquired by Pfizer Inc. in 2014. TICOVAC was granted FDA approval on August 13, 2021.